Statistical Analysis of Work Sampling Data: Master Work Measurement Techniques

Question 1

Which type of probability distribution is commonly used to model the time between occurrences of work elements in work sampling?

Accepted Answer

Poisson distribution

Answer

Normal distribution

Answer

Binomial distribution

Answer

Uniform distribution

Question 2

Which statistical method do we employ to determine the proportion of time spent on a specific activity based on work sampling observations?

Accepted Answer

Confidence interval

Answer

Estimation of variance

Answer

Hypothesis testing

Answer

Decision theory

Question 3

What is the formula utilized to compute the confidence interval for a proportion derived from work sampling data?

Accepted Answer

p ± z * √(p * q / n)

Answer

z * √(p * q) / n

Answer

n * z * √(p * q / p)

Answer

p * q / n

Question 4

How do we enhance the precision of a confidence interval?

Accepted Answer

Increase sample size

Answer

Lower confidence level

Answer

Decrease population variability

Answer

Use a different statistical method

Question 5

What is the primary purpose of hypothesis testing in work sampling?

Accepted Answer

To determine if there is a meaningful difference between two or more proportions

Answer

To estimate the population proportion

Answer

To ascertain the sample size for a work sampling study

Answer

To evaluate the reliability of a work sampling system

Question 6

Which measure of central tendency is most suitable for skewed work sampling data?

Accepted Answer

Median

Answer

Mean

Answer

Mode

Answer

Range

Question 7

Which of the following is a fundamental assumption of work sampling?

Accepted Answer

Observations are independent and unaffected by the observer's presence.

Answer

Work elements are constant over time.

Answer

The data is normally distributed.

Answer

The sample size is large enough to ensure statistical validity.

Question 8

What is the primary purpose of using a confidence interval in work sampling?

Accepted Answer

To estimate the true mean proportion of time spent on a given activity.

Answer

To determine the minimum sample size needed.

Answer

To test hypotheses about population parameters.

Answer

To compare the proportions of time spent on different activities.

Question 9

What is the key difference between a stratified random sample and a simple random sample?

Accepted Answer

Stratified random sampling ensures representation from different subgroups within the population.

Answer

Simple random sampling is more likely to introduce bias.

Answer

Stratified random samples are always larger than simple random samples.

Answer

There is no difference between the two types of samples.

Question 10

Which statistical test is appropriate for comparing the mean proportions of time spent on two different activities?

Accepted Answer

t-test

Answer

Z-test

Answer

Chi-square test

Answer

ANOVA

Question 11

Describe the distinction between a random sample and a systematic sample.

Accepted Answer

In a random sample, each element has an equal chance of being selected, while in a systematic sample, elements are chosen at regular intervals.

Answer

Systematic sampling is always larger than random sampling.

Answer

There is no difference between the two types of samples.

Answer

Random samples are more likely to be biased.

Question 12

To reduce the sample size in work sampling, it is effective to:

Accepted Answer

Decrease the confidence level

Answer

Increase the desired precision of the estimate

Answer

Increase the expected proportion of observations in a specific category

Answer

Increase the duration of each observation

Question 13

The primary objective of statistical analysis in work sampling is to:

Accepted Answer

Make inferences about the population based on sample data

Answer

Determine the average time spent on each work activity

Answer

Identify areas for improvement in the work process

Answer

Calculate the standard deviation of the work sampling data

Question 14

In work sampling studies, which strategy is most effective in minimizing the risk of observer bias?

Accepted Answer

Providing comprehensive training to observers

Answer

Limiting the sample size

Answer

Observing only high-activity periods

Question 15

To calculate the standard deviation of a work element from work sampling data, which statistical technique should you use?

Accepted Answer

Sample variance

Answer

Sample mean

Answer

Chi-square test

Answer

Analysis of variance

Question 16

What is the primary purpose of utilizing confidence intervals in the statistical analysis of work sampling data?

Accepted Answer

Determining the precision of estimated mean values

Answer

Estimating the mean value of a work element accurately

Answer

Testing hypotheses about the statistical control of a process

Answer

Calculating the standard deviation of a work element

Question 17

When calculating the sample size for work sampling, which formula should you use?

Accepted Answer

n = (Z^2 * s^2) / (E^2)

Answer

n = (E^2 * s^2) / (Z^2)

Answer

n = (Z * E) / (s^2)

Answer

n = (Z * s^2) / (E^2)

Question 18

How do you calculate the work factor from work sampling data?

Accepted Answer

Ratio of productive observations to total observations

Answer

Ratio of unproductive observations to total observations

Answer

Difference between productive and unproductive observations

Answer

Sum of productive and unproductive observations

Question 19

In a work sampling study, a confidence interval of (0.4, 0.6) is calculated for the proportion of time spent on a specific task. What does this interval imply in practical terms?

Accepted Answer

The true proportion of time spent on the task is likely between 40% and 60%, with a 95% level of confidence.

Answer

The proportion of time spent on the task is exactly 50%.

Answer

No conclusions can be drawn about the true proportion of time spent on the task based on this confidence interval.

Question 20

When designing a work sampling study, how should the sample size be determined?

Accepted Answer

Based on the desired confidence level and precision

Answer

Randomly selected

Answer

Using a large sample to ensure accuracy

Answer

Based on the number of employees being observed

Question 21

In work sampling analysis, what is the primary purpose of constructing confidence intervals?

Accepted Answer

To estimate the true proportion of time spent on specific activities

Answer

To determine the variability of the observed data

Answer

To calculate the mean time spent on various activities

Answer

To predict future work performance

Question 22

Which of the following is a key advantage of work sampling over other work measurement techniques?

Accepted Answer

Can be conducted without interrupting ongoing work processes

Answer

Provides highly detailed observations of work activities

Answer

Requires extensive training for accurate data collection

Answer

Eliminates the potential for observer bias

Question 23

In a statistical hypothesis test, what does the null hypothesis represent?

Accepted Answer

The initial assumption, typically stating no significant difference or effect

Answer

The alternative assumption, stating a significant difference or effect

Answer

The conclusion drawn from the test

Answer

The probability of rejecting the null hypothesis

Question 24

When interpreting the results of a hypothesis test, what does a p-value less than the level of significance indicate?

Accepted Answer

The null hypothesis is rejected, and the alternative hypothesis is supported

Answer

The null hypothesis is accepted, and the alternative hypothesis is rejected

Answer

The test is inconclusive, and more data is needed

Answer

The results are not statistically significant

Question 25

What is the key difference between a one-tailed and a two-tailed hypothesis test?

Accepted Answer

One-tailed tests consider one direction of the alternative hypothesis, while two-tailed tests consider both directions

Answer

One-tailed tests are more powerful, while two-tailed tests are less powerful

Answer

One-tailed tests are used for exploratory research, while two-tailed tests are used for confirmatory research

Answer

Two-tailed tests are more likely to result in a Type II error

Question 26

In work sampling, why is a random number generator used?

Accepted Answer

To ensure that observations are independent and unbiased

Answer

To increase the accuracy of the results

Answer

To reduce the time spent on observation

Answer

To make the study more efficient

Question 27

To determine the proportion of a work activity observed from work sampling data, which statistical measure should be used?

Accepted Answer

Sample proportion

Answer

Population size

Answer

Variance

Answer

Standard deviation

Question 28

What is the main purpose of a confidence interval in work sampling analysis?

Accepted Answer

To estimate the true population parameter with a specified margin of error

Answer

To predict future work activity levels

Answer

To determine the significance of observations

Question 29

Which work sampling observation method captures the status of a worker at a specific point in time?

Accepted Answer

Snapshot observation

Answer

Interval observation

Answer

Activity sampling

Answer

Continuous observation

Question 30

When is stratified random sampling advantageous in work sampling?

Accepted Answer

When the population exhibits significant heterogeneity

Answer

When the work environment is highly dynamic

Answer

When observations are time-independent

Answer

When the sample size is small

Question 31

Which data visualization tool is most appropriate for displaying the frequency distribution of work sampling data?

Accepted Answer

Histogram

Answer

Bar chart

Answer

Pie chart

Answer

Scatter plot

Question 32

What is a central assumption of the normal distribution as applied to work sampling?

Accepted Answer

The data follows a symmetrical, bell-shaped curve

Answer

The observations are independent

Answer

The sample size is sufficiently large

Answer

The mean and standard deviation are known

Question 33

Which hypothesis test is employed to determine if the proportion of productive work differs significantly from a known value?

Accepted Answer

Z-test for proportions

Answer

T-test

Answer

Chi-square test

Answer

ANOVA

Question 34

What is the primary purpose of establishing a confidence level in a hypothesis testing procedure?

Accepted Answer

To control the probability of rejecting a true null hypothesis

Answer

To increase the sample size

Answer

To determine the significance level

Question 35

In random observation sampling, what is observed?

Accepted Answer

Workers' activities at random intervals

Answer

Workers' most productive times

Answer

Workers' idle time

Answer

Workers' busiest times

Question 36

When analyzing work sampling data, what is the primary purpose of using a confidence interval?

Accepted Answer

Estimate the true proportion of activities with a defined confidence level

Answer

Calculate the variance of the activity times

Answer

Determine the sample size for the study

Question 37

In statistical analysis of work sampling data, which of these is NOT a step?

Accepted Answer

Calculating the mean activity duration

Answer

Testing hypotheses about the data

Answer

Constructing a confidence interval

Answer

Estimating the population proportion

Question 38

In work sampling analysis, what is the most frequently used measure of central tendency?

Accepted Answer

Mean

Answer

Mode

Answer

Standard deviation

Answer

Median

Question 39

Which statistical test is used to determine if the observed activity proportions deviate significantly from a predetermined standard?

Accepted Answer

Chi-square test

Answer

ANOVA

Answer

t-test

Answer

Regression analysis

Question 40

What is the key advantage of using work sampling over other work measurement techniques?

Accepted Answer

Less disruptive to work processes

Answer

Less expensive

Answer

Faster

Answer

More accurate

Question 41

Which of these is a prevalent application of work sampling in industrial settings?

Accepted Answer

Determining standard times for assembly tasks

Answer

Evaluating the impact of advertising campaigns

Answer

Assessing employee performance

Answer

Forecasting customer demand

Question 42

What is the primary purpose of constructing a confidence interval based on work sampling data?

Accepted Answer

To estimate the true proportion of an activity within a defined margin of error

Answer

To determine the necessary sample size for the study

Answer

To evaluate whether the observed proportion is statistically different from a hypothesized value

Question 43

In work sampling, what statistical distribution is used to determine the critical value for calculating the confidence interval of a sample proportion?

Accepted Answer

Standard normal distribution (z-distribution)

Answer

F-distribution

Answer

Chi-square distribution

Answer

Student's t-distribution

Question 44

What is the primary objective of a hypothesis test in the context of work sampling?

Accepted Answer

To determine if there is a statistically significant difference between the observed proportion and a hypothesized value

Answer

To estimate the true proportion of an activity

Answer

To validate the accuracy of the sampling methodology

Question 45

In a work sampling study, which of the following represents the null hypothesis?

Accepted Answer

The hypothesized proportion is equal to the observed proportion

Answer

The hypothesized proportion is greater than the observed proportion

Answer

The hypothesized proportion is less than the observed proportion

Question 46

When conducting hypothesis testing with work sampling data regarding the proportion of an activity, which statistical test is generally most appropriate?

Accepted Answer

Z-test

Answer

F-test

Answer

Chi-square test

Answer

Student's t-test

Question 47

What is the main purpose of conducting a pilot study prior to a full-scale work sampling study?

Accepted Answer

To estimate the proportion of an activity and determine an appropriate sample size for the main study

Answer

To validate the hypothesis of interest

Question 48

In work sampling, what is the key difference between random and systematic observations?

Accepted Answer

Random observations are taken at random intervals, while systematic observations are taken at predetermined intervals

Answer

Random observations are more precise than systematic observations

Question 49

What is the purpose of stratification in the context of work sampling?

Accepted Answer

To divide the population into subgroups based on relevant characteristics to improve the accuracy of the analysis

Answer

To calculate the confidence interval for the sample

Answer

To select a random sample from the population

Question 50

What is a key advantage of using weighted averages in work sampling?

Accepted Answer

It allows for different strata to have varying weights in the overall calculation, considering their relative importance or contribution

Answer

It reduces the required sample size

Answer

It guarantees the accuracy of the estimate